Pop up traffic divider



United States Patent Joseph W. Bowersox Monterey, California Nov. 14,1968 Sept. 29, 1970 Terra Engineering Company, Inc., a corporation ofDelaware Inventor Appl. No. Filed Patented Assignee References CitedUNITED STATES PATENTS Primary Examiner-Nile C. Byers, Jr. Attorney-Lothrop and West ABSTRACT: A pop up traffic divider for use on a highwayhas a housing buried flush with the highway and containing a casing alsoflush with the highway and encompassing a column supported on the casingbottom and at top flush with the highway. An annular piston is disposedbetween the casing and the column and is moved up and down bydifferential pressure of fluid such as air. On the piston is aresilient, deformable tube retracted within the casing and expelledtherefrom by movement of the piston. The upper end of the column and ofthe casing afford a rounded body or bodies over which the extended,deformable and resilient tube can be bent without injury. 1

III

Patented Sept. 29, 1970 v V 3,530,775

Sheet 1 012 INVENTOR. 3 JOSEPH M4 iowiiiax Patented Sept. 29, 19703,530,775

Sheet 2 012 FIG-3 POP UP TRAFFIC DIVIDER In modern traffic control,particularly on multilane highways, there are various means of demarkingturning points and of marking the boundary between adjacent highwaylanes. There are also ways of demarking different lanes at differenttimes in order to accommodate variances in the flow of traffic. Sundrydevices for this purpose are manually positioned and shifted andremoved. This is an ex pensive and sometimes dangerous operation. Themarking devices offer, in some instances, hazards to driving.

It is an object of the invention to provide an improved traffic dividerwhich is permanently installed and which is movable between a retractedposition substantially concealed beneath the highway to a projectedposition forming a visible and actual physical barrier above thehighway.

Another object of the invention is to provide a pop up traffic dividerwhich can be actuated from a remote point.

Another object of the invention is to provide a pop up traffic dividerof sufficient durability and stamina as to withstand abuse in traffic.

Another object of the invention is to provide a pop up traffic dividerwhich is entirely safe and does not increase the traffic hazard norinterfere with emergency operation.

Another object of the invention is to provide a pop up traffic dividerwhich is relatively inexpensive to install and maintain under adverseweather and traffic conditions.

A further object of the invention is to provide a pop up traffic dividerwhich can readily be repaired or replaced when necessary.

Another object of the invention is to provide a pop up traffic dividerhaving a projecting and retracting tube of special characteristics tofit it for long-continued service despite onerous conditions.

Another object of the invention is in general to provide an improved popup traffic divider.

Other objects of the invention together with the foregoing are attainedin the embodiment of the invention described in the accompanyingdescription and illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevation of an installation of a number of my trafficdividers in a highway, the highway being shown in cross-section on avertical plane;

FIG. 2 is a cross-section, the plane of which is indicated by the line2-2 of HG. 1, with the scale substantially enlarged and with a portionof the figure broken away to reduce its size and other portions brokenaway to show the interior arrangement;

HO. 3 is a side elevation of the tube with portions broken away toillustrate the interior arrangement; and

FIG. 4 is a cross section, in part diagrammatic, showing the interactionof a vehicle wheel with a pop up traffic divider constructed pursuant tothe invention herein.

In a typically successful installation one or a number of dividers 6 and7 are provided. If a number are installed, all of them are substantiallyidentical and are installed, usually in a linear series, below andwithin the pavement 8 of a highway or the like having a traffic surface9. A description of one device applies to all. Preferably there isprovided in and below the material of the highway 8 an exterior housing11. This is conveniently a circular cylindrical, tubular member of metalor plastic. In this instance the housing is of metal long enough toextend substantially vertically into the ground and being symmetricalabout a vertical axis 12. At its upper end the housing 11 is providedwith a reinforcing collar 13 conveniently held in place by a weld l4 andis positioned so that the upper surface of the collar !3 issubstantially flush with the surface 9 of the highway. At its lower endthe housing 11 is closed by a plug 16 conveniently held in place bywelds 17. The plug 16 closes the bottom end of the housing against theelements so that there is afforded a segregated enclosure or pocket.

Designed to fit into the housing 11 is a casing 18, also of circularcylindrical configuration, disposed concentrically about the axis 12.The casing extends downwardly into close contact or abutment with theplug 16 and at its upper end extends toward the collar 13 to join aconical ring 19 to which it is secured by welding 20. A moderately hardbut flexible annulus 21 is secured to a flanged metal disc 22 held onthe ring 19 by fasteners 23, a skirt 24 being clamped as a gasketbetween the ring 19 and the collar 13. The ring 19 is referred to hereinas substantially flush with the surface of the highway. While thedrawing (FIG. 2) is approximately to scale and while in fact the ring 19is above the highway surface, the amount the ring extends above thesurface is small compared to the diameter of vehicle wheels passingnearby and is of about the same upward projection as is encountered inconnection with the usual traffic lane marker buttons. This constructionleaves a small annular space 25 between the housing 11 and the casing18.

At its lower end the casing 18 is closed by a disc 26 held in place by aweld 27. The disc 26 is also held by a weld 28 to a central column 29preferably of tubular form, the disc and column thus being virtuallyintegral. The column is concentric with the axis 12 and at its upper endreceives a cap 31 having a central boss 32 seated within the column. Theboss 32 has a rounded rubber-like top 33 secured to a plate 34 held tothe cap by fasteners 35. The top, although actually above the surface ofthe highway, is substantially flush therewith. That is, the top 33extends above the highway about as much as the normal highway lanemarking buttons. The cap 31 is of a diameter to approach closely theinterior diameter of the ring 19 to leave an annular openingtherebetween.

For securing the cap 31 in position and for holding the column 29 andits base 26 in removable contact with the plug 16 and to maintain theparts in assembled operating relationship, there is a rod 36 passedcentrally through the column along the axis 12. The rod is preferablyprovided with a head 37 designed to receive any of the customarywrenches such as an Allen wrench and has threads 38 at its lower endengaged with an internally threaded boss 39 centrally disposed on theplug 16. When a wrench tightens the rod 36, the cap and column are heldfirmly in position so that the cap is in weightsupporting andtransmitting relationship with the rest of the installation. The cap andcolumn are strong enough to support the weight and impact of any highwayvehicle. When the wrench reversely operates the rod 36, the cap may beremoved and the column and casing 18 can then be removed from thehousing.

Situated in the annular space 41 between the outside of the column 29and the inside of the casing 18 is a piston 42. The piston has a lowerface 43 in the bottom position thereof adapted to abut a boss 44 on thedisc 26. The piston 42 is designed to slide on the column 29 and forthat reason has spaced apart interior faces 46. Likewise, the pistonslides on the interior of the casing 18 and so has a cooperating face47. The faces 46 and 47 are provided with O-rings 48 so that theslidable piston is sealed against leakage to and from the annular space41.

Secured to the piston 42 is a special tube 51. Under some conditions thepiston 42 and the tube 51 are made integrally, but for convenience underpresent circumstances the tube and piston are separately manufacturedand are then joined together on a serrated periphery 52 of the piston 42by a suitable adhesive such as cement. The tube, as particularly shownin FIG. 3, is an especially manufactured annular body designed to take agreat deal of flexing and to be readily deformable, although resilientso as to return after deformation substantially to its original shapeand size. Practically, l have made a tube able to withstand substantialabuse by providing an inner tube 53 of an elastomeric material such assynthetic rubber and with a band of fibers 54 around such inner tube 53.The fibers 54 are arranged with the axis of each fiber parallel to thecentral axis 56 of the tube, so that the fibers extend lengthwise orlongitudinally of the tube. Around the longitudinal fibers 54 1 providea covering 57 of additional elastomeric material which in turn issurrounded by circum ferentially extending fibers 58. Around this layerof fibers 58 is imposed a further layer 59 of elastomeric materialitself surrounded with circumferentially wound or extending fibers 61.Finally, to provide a smooth exterior, the fibers 61 are surrounded byan elastomeric layer 62. The result of this construction is a tube 51 ofa carefully controlled predetermined size and smoothness as to bothinterior and exterior surfaces, a tube which is very nearly circularcylindrical throughout its entire length and a tube able to deform anddeflect numerous times without injury, yet one which is sufficientlyresilient or elastic as to return after deflection substantially to itsoriginal configuration.

The tube 51 is of such height that when the piston 42 is at its bottommost location, the top or rim 63 of the tube is approximately flush withthe surface of the top 33 and thus is not exposed and visible but ratheris retracted and virtually unnoticeable.

While many different means may be utilized to move the piston 42 withinits annular space 41, present preference is to utilize compressed airfor this purpose and so to subject the piston to differential pressure.For that reason, as diagrammatically shown in FIG. 2, there is a controlvalve 64 governing flow from a source 66 of air under pressure and to awaste or sink 67 (such as the atmosphere) for air under pressure. Thevalve 64 can also connect either the inlet 66 or the outlet 67 to acontrol pipe 68 which extends to a nipple 69 intersecting the wall ofthe housing 11 and communicating with the annular space 25 therein. Asimilar nipple 71 in an opposite location in the wall of the housing hasa connection 72 (FIG. 1) to the adjacent housing in a series. If aseries is not utilized, the nipple 71 can be omitted or capped. Thevalve 64 thus can supply air under pressure to the annular space 25, butthe air cannot escape at the top because of the skirt 24 and also cannotflow improperly at the bottom because of the provision of an O-ring 73in the disc 26. However, there are apertures 74 through the wall of thecasing 18 so that pressure air can enter the annular space 41 in thechamber 76 beneath the piston 42. If the valve 64 is reversed, then airunder pressure within the interior spaces can discharge through theoutlet 67.

The valve- 64 likewise can connect either the supply 66 or the discharge67 to a line 77 having a fitting 78 joined to a tube 79 leading toanother fitting 81 opening into a passage 82 formed in the plug 16. Thepassage 82 continues through the central boss 39 into the interior ofthe column 29. A plug 83 provides for drainage when removed. There is noflow to or from the upper end of the column 29 except through a passage84. The passage 84 has an outlet 87 leading into the annular space 41above the piston 42. Leakage is prevented by a packing ring 85 and abackup ring 86.

When the valve 64 is operated in one sense there is afforded a superiorair pressure beneath the piston 42, which is driven upwardly in thecasing 18, lifting the tube 51 with it, until such time as the piston 42is in abutment with the under side of the cap 31. In that relationshipof parts the tube 51 extends above the highway a substantial amount asindicated in FIG. 1. The tube is normally of a bright, highly visible,light reflecting finish so that it serves as an easily observeddemarcation or divider for a turning point or for adjacent trafficlanes. When the valve 64 is reversed, then the chamber 41 is suppliedwith air under pressure through the line 77, the tube 79, the passage 82and the interior of the column 29, as well as the passages 84 and 87. Atthe same time, the chamber 76 below the piston is relieved of itspressure through the openings 4, the annular space 25 and the nipple 69as well as the line 68. Thus by operating the valve 64 one way or theother. the tube cannot only be extended to stand upright above thehighway, but can be retracted by power to its FIG. 2 position and heldout of sight within or below the highway. In fact, all of the markers ina series can be so handled and can be simultaneously controlled from aremote or central point.

The top edges of the annulus 21 and of the top 33 are preferably madesharp and to contact the tube 51 closely not only to keep out andprevent wedging of extraneous material but to act as scrapers duringdownward motion to strip the tube surface of adhering material.

When the tube 15 extended it 18 sometimes inadvertently hit by adjacentvehicles or in emergency is purposely run into or over. Under thoseconditions the tube simply yields. Following the release of the contact,the tube springs back to its initial location without any particularharm. The lower end of the tube is well anchored and held within theburied portion of the structure so that the tube is not readilydislodged from the piston and cannot come off and fly about to causeinjury under such circumstances. More particularly, severe tests haveshown that when a skidding or locked vehicle wheel 91 (FIG. 4)encounters the upstanding tube and slides over it above the ring 21 andthe top 33, the tube itself bends readily over and also deforms therubber-like ring 21 and the top 33 and is folded flat. The upper side ofthe tube is held directly against the lower side of the tube, which inturn is pressed against the surface of the highway. Tests indicate thatthe coefficient of friction between the rapidly advancing butnon-rotating vehicle tire 91 and the outside of the tube 51 is less thanthe coefficient of friction between the outside of the tube and thehighway surface or adjacent mechanism. Thus, the tube, when in theposition shown in FIG. 4, is held by the vehicle weight in closejuxtaposition to the highway and is retained by the friction between thetube and the highway. The tube is not stripped off or torn out of itsmounting. After the vehicle wheel slides or rolls off of it, the tube issufficiently resilient as to spring back into circular-cylindrical formand into its initial upright position. The ring 21 and the top 33likewise return substantially to normal to resume their protecting andscraping functions. The tube can then be withdrawn and projected} asbefore.

Iclaim:

l. A pop up traffic divider for use on a highway comprising a casingadapted to be disposed with the upper end thereof substantially flushwith the highway surface, a column within said casing and adapted to bedisposed with the upper end thereof substantially flush with the highwaysurface, an annular piston disposed between and slidably engaging saidcasing and said column, a resilient deformable tube disposed betweensaid casing and said column and having the lower end of said tube joinedto said piston, and means for subjecting said piston to differentialpressure.

2. A pop up traffic divider as in claim 1 including a housing adapted tobe disposed with the upper end thereof substantially flush with thehighway surface and adapted to receive said casing telescopically, andmeans for removably securing said casing to said housing.

3. A pop up traffic divider as in claim 2 including means forestablishing a pressure fluid connection between said casing and saidhousing.

4. A pop up traffic divider as in claim 1 in which said I column ishollow and is included in a pressure fluid circuit.

5. A pop up traffic divider as in claim 1 in which said columnterminates at the upper end thereof in a cap in contact with theinterior of said tube.

6. A pop up traffic divider as in claim 1 in which said tube is anelastomeric body incorporating reinforcing fibers.

7. A pop up traffic divider as in claim 6 in which some of said fibersextend around said tube and some of said fibers extend along said tube.

8. A pop up traffic divider as in claim 1 in which the upper portions ofsaid column and of said casing adjacent said tube are rounded.

9. As an article of manufacture, a tube for use in a pop up trafficdivider comprising an elastomeric body having incorporated thereinreinforcing fibers extending longitudinally of the tube andcircumferentially of said tube.

10. A pop up traffic divider as in claim 1 in which a cap and a ring areprovided in substantially edge contact relationship with the interiorand exterior peripheries of said tube to serve as wipers therefor.

